Dexodel Plus

Approved Indications:

• Symptomatic Relief of Common Cold and Allergic Rhinitis:
• Relief of nasal congestion (due to phenylephrine).
• Suppression of cough associated with upper respiratory tract infections (due to dextromethorphan).
• Alleviation of allergy-related symptoms such as sneezing, runny nose, and watery eyes (due to triprolidine).
• Seasonal Allergic Rhinitis: Management of sneezing, rhinorrhea, and nasal congestion.
• Upper Respiratory Tract Infections: Symptomatic treatment to improve patient comfort.

Off-label / Clinically Accepted Uses:

• Temporary relief of symptoms related to hay fever and other respiratory allergies.
• Adjunct treatment for mild sinusitis symptoms.

• Route: Oral administration.
• Adults and Children ≥12 years:
• Typical dose: 1 to 2 tablets or capsules every 4 to 6 hours as needed.
• Maximum daily dose: Do not exceed 8 doses (varies by formulation).
• Children <12 years:
• Use is generally not recommended unless specified by healthcare provider.
• Elderly:
• Use with caution due to increased risk of side effects; start with lowest effective dose.
• Renal/Hepatic Impairment:
• Dose adjustment may be necessary in severe impairment; consult a healthcare professional.
• Administration Notes:
• Take with water.
• Avoid taking with other sympathomimetic or sedating medications.
• Avoid alcohol during treatment.

• Dextromethorphan: Acts centrally on the medullary cough center as an NMDA receptor antagonist and sigma-1 receptor agonist, suppressing the cough reflex without significant respiratory depression.
• Phenylephrine: A selective α1-adrenergic receptor agonist causing vasoconstriction of nasal mucosal blood vessels, reducing swelling and nasal congestion.
• Triprolidine: A first-generation antihistamine blocking H1 receptors, reducing allergic symptoms such as sneezing, itching, and rhinorrhea; also exerts sedative effects due to central nervous system penetration.

Together, these agents provide multi-symptom relief by suppressing cough, reducing nasal congestion, and controlling allergic symptoms.

• Absorption: Well absorbed orally for all three agents.
• Distribution:
• Dextromethorphan crosses the blood-brain barrier to exert central effects.
• Triprolidine readily crosses the blood-brain barrier causing sedation.
• Metabolism:
• Dextromethorphan is extensively metabolized in the liver by CYP2D6 to dextrorphan (active metabolite).
• Phenylephrine undergoes significant first-pass metabolism reducing systemic bioavailability.
• Triprolidine is metabolized primarily by the liver.
• Half-life:
• Dextromethorphan: Approximately 3–4 hours.
• Phenylephrine: About 2.5 hours.
• Triprolidine: 4–6 hours.
• Elimination: Primarily renal excretion of metabolites.

• Pregnancy:
• Phenylephrine: Category C; risk due to vasoconstriction; use only if benefits outweigh risks.
• Dextromethorphan and triprolidine: Limited human data; caution advised.
• Lactation:
• Dextromethorphan and phenylephrine are excreted in breast milk in small amounts; avoid or use with caution.
• Triprolidine may cause sedation in nursing infants; caution recommended.

• Primary Class: Combination cold and allergy medication.
• Subclasses:
• Dextromethorphan: Antitussive.
• Phenylephrine: Nasal decongestant (sympathomimetic).
• Triprolidine: First-generation antihistamine.

• Known hypersensitivity to dextromethorphan, phenylephrine, triprolidine, or any excipients.
• Use within 14 days of monoamine oxidase inhibitors (MAOIs).
• Severe hypertension or severe coronary artery disease (due to phenylephrine).
• Narrow-angle glaucoma (due to triprolidine).
• Severe coronary insufficiency.
• Concurrent use of other sympathomimetic agents.
• Hyperthyroidism.

• Use caution in patients with hypertension, diabetes, heart disease, hyperthyroidism, or glaucoma.
• Risk of increased blood pressure and arrhythmias from phenylephrine.
• CNS depression and sedation from triprolidine; avoid activities requiring alertness.
• Risk of serotonin syndrome if combined with serotonergic drugs (due to dextromethorphan).
• Avoid alcohol and CNS depressants.
• Monitor for allergic reactions.
• Use caution in elderly and pediatric populations.

Common:

• Drowsiness or sedation (triprolidine).
• Dry mouth.
• Nervousness or dizziness.
• Nausea or gastrointestinal discomfort.
• Headache.

Serious/Rare:

• Hypertension or tachycardia.
• Palpitations.
• Allergic reactions including rash, swelling.
• Hallucinations or confusion (rare, related to dextromethorphan overdose).
• Urinary retention (especially in elderly or those with prostate hypertrophy).

• MAO inhibitors: Risk of hypertensive crisis or serotonin syndrome.
• Other CNS depressants: Additive sedation with alcohol, benzodiazepines.
• Sympathomimetics: Additive cardiovascular effects (e.g., increased blood pressure).
• Serotonergic drugs: Increased risk of serotonin syndrome.
• Anticholinergic drugs: Additive dry mouth, urinary retention.
• CYP2D6 inhibitors may increase dextromethorphan plasma levels.

• Current guidelines emphasize avoiding combination with MAOIs and monitoring cardiovascular risks.
• Warning updates regarding serotonin syndrome risk with concomitant serotonergic agents.
• Recommendations to limit use duration to short-term (usually ≤7 days) to prevent adverse effects.

• Store at 20°C to 25°C (68°F to 77°F).
• Protect from moisture and light.
• Keep container tightly closed.
• Do not freeze.
• Keep out of reach of children.